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annual production accounted for by alfalfa. In 1990, alfalfa accounted for 31 percent of total • <br />production. This apparent reduction in alfalfa may be partly due to climatic conditions (the <br />Wadge Pasture Comparison area in 1990 had 34.5 percent of total production in alfalfal and <br />partly due to the effects of grazing. It may be that the effects of four years of drought <br />conditions are only in 1 E)90 being manifested in the deep-rooted alfalfa. The difference <br />between the Wadge Pasture and the Wadge Pasture Comparison in alfalfa proportion 13.5 <br />percent) may reflect the effects of grazing or may reflect na statistical difference. <br />Shrub Density <br />Figure 3 graphically presents shrub density totals for reclaimed areas sampled in 1990. As <br />can be seen, the highest densities by far were observed in the 1983 Wolf Creek area. This <br />area has shown high density since it was first sampled in 1987 (see 1987 Seneca II Mine <br />Revegetation Monitoring Reportl. In 1987, this area had the lowest r:over and lowest <br />production of all areas s,9mpled that year, suggesting that there had existed, in the early years, <br />sufficient physical and competitive "space" to allow shrub seed to germinate and establish <br />without hindrance from herbaceous growth. Also, whereas in the otfrer reclaimed areas it is <br />typical to have mountain snowberry the most abundant of all the shrubs, in the 1983 Wolf • <br />Creek area, the density of mountain snowberry is minor compared to both basin big sagebrusK'~ <br />and mountain big sagebrush (Table 26). It is interesting to further note that as of 1990, cover <br />and production levels in the 1983 Wadge area, so low in 1987, werr: in the upper echelon of <br />all reclaimed areas, and that species density was the highest of any area older than two years <br />land past the weedy annual stage, see Species Diversity and Composition belowl. <br />The next highest shrub density levels were observed in the Wadge Pasture and Wadge Pasture <br />Comparison areas. The Wadge Pasture Comparison area was carefully chosen to match the <br />Wadge Pasture in age and history so as to serve as a good control for the Wadge Pasture <br />grazing experiment. Higher shrub densities observed in the Wadge Pasture during 1988 and <br />1989 compared to the nearest comparable areas were apparently illu::ory since the shrub <br />density levels observed in 1990 in the Wadge Pasture Comparison area were equal to those of <br />the Wadge Pasture. The effects of grazing on shrub establishment in this experiment are <br />apparently unseen as yet., though shrub vigor appears to be higher. V <br />Shrub density levels are fairly high in the 1988 Wolf Creek area and only a little over one-third <br />as much in the 1988 Wadge. This would seem to correlate with the greater tibundance of • <br />open soil and scarcity of litter in the 1988 Wolf Creek as compared to the 1988 Wadge area. <br />16 <br />